TEL AVIV – An al-Qaida-allied group in the Gaza Strip claimed to WND that there have been arrests of jihadists in both Pakistan and Afghanistan as part of the probe into yesterday’s Boston Marathon explosions.

The arrests could not be immediately confirmed.

Members of Gaza’s Jihadiya Salafia group further said that al-Qaida is being credited for the attack in its affiliated online forums.

The Gaza sources told WND the online al-Qaida forum messages claimed the bombings were an al-Qaida response to a U.S. military airstrike that killed a high-profile Taliban leader and four other Taliban members last week near Afghanistan’s eastern border with Pakistan.

Jihadia Salafia represents al-Qaida in Gaza.

It was not immediately clear whether the Internet claims should be taken seriously or simply represented jihadists utilizing the explosions.

President Obama was careful not to use the words “terror” or “terrorism” as he spoke at the White House yesterday, while an administration official said the bombings were being treated as an act of terrorism.

“We will find out who did this. We’ll find out why they did this,” the president said. “Any responsible individuals, any responsible groups, will feel the full weight of justice.”

The FBI has taken charge of the investigation. A 20-year-old Saudi national reportedly was taken into custody near the scene of the attack.

The New York Post reported the suspect was being questioned by the FBI and local police at Boston’s Brigham and Women’s Hospital, where he was under heavy guard while being treated for shrapnel injuries to his leg sustained in one of the blasts.

A large group of federal and state law enforcement agents reportedly raided an apartment in a building in the Saudi man’s hometown of Revere, Mass.

CNN reported the search took place by consent, according to a federal law enforcement source, meaning no search warrant was needed.

The Pakistani Taliban today reportedly denied any role in the marathon bombings.

Media blame right-wing

While the initial indications may point toward Islamic terrorism, some in the media have been speculating it could have been a domestic attack, with some analysts suggesting “right wing extremists” were involved.

Bergen said al-Qaida often uses hydrogen peroxide explosives, while another type of explosion might signal that a “right-wing extremist” was involved.

The explosions, Bergan said, reminded him of the Oklahoma City bombing, for which Timothy McVeigh was arrested, convicted and executed.

And Bergen said it also brought to mind other “right-wing” attacks.

“Right-wing groups trying to attack, for instance – trying to attack the Martin Luther King parade in Oregon in 2010,” he said. “So, if it is a device of some kind, you know, we shouldn’t leap to conclusion about where it’s coming from.”

Also today, the U.K. Independent ran a report quoting a terror expert who claimed the marathon attack has hints the handiwork of a right-wing terrorist attack rather than al Qaida-inspired extremism.

Richard Barrett, the former United Nations coordinator for the al-Qaida and Taliban monitoring team, said it was too early to say who was to blame for the marathon blasts.

But Barrett, who has served with Britain’s MI5, MI6 and the Foreign Office, told the Independent the timing of the attack on Patriots’ Day and the relatively small size of the devices suggested the work of a domestic extremist.

Barrett, who is now senior director at the Qatar International Academy for Security Studies, said: “At the moment it looks more likely that it was a right-wing terrorist incident, rather than an al-Qaida attack because of the size of the devices.”

He added: “This happened on Patriots’ Day, it is also the day Americans are supposed to have their taxes in, and Boston is quite a symbolic city. These are all little indicators.”

Boston Police Commissioner Edward Davis said authorities had received “no specific intelligence that anything was going to happen” at the race.